When should life be protected? How could anti-aging techniques, genetic engineering, and mood-controlling drugs change human nature? What moral obligations do drug companies have to provide life-saving medications at low cost to the poor? Can people with severe mental illness truly give informed consent to participate in research?

These are just a few of the thorny questions that bioethicists are paid to consider - and with the sequencing of the human genome, the advent of mammalian cloning, and continued increases in spending on biomedical research, opportunities in the field are expanding.

David Magnus, graduate studies director and professor of bioethics at the University of Pennsylvania's Center for Bioethics, says, "The field is absolutely growing. It's hard to assess, because there is not a clear sense [of how to define a bioethicist], but master's programs have sprung up all over and the number of students enrolled is booming." Penn's master's program started four years ago with 15 students; it now has 32, and the school is considering adding more slots.

The number of publications devoted exclusively to bioethics tripled between 1987 and 1997. The study of ethics issues related to the Human Genome Project was funded by the government from the project's outset, with a total of $76.8 million spent by 2000. Moreover, there are now over 100 academic bioethics research centers.

According to Magnus, the growth results from increased opportunities to publish in major journals like the Journal of the American Medical Association and Science as well as in specialty journals, and from increased grant money for bioethics research. Research ethics is a particularly hot area. "It's booming," says Magnus, who notes that the institutional review boards that oversee research in human subjects are mandated to consider ethical questions, and often hire bioethicists. Major academic medical centers - including Penn and Duke University - have had research projects shut down by the government for failing to deal properly with ethical concerns, and the FDA won't approve drugs if it believes that researchers have not treated human subjects ethically.

The accounting firm Price Waterhouse has even begun offering "ethics audits" and hiring bioethicists to run them. "In general, a big outfit will want to do one every few years just to be sure everything's OK," says Magnus.

Public interest in the field is also at an all-time high. Magnus notes that Bioethics.net, the Web site of the American Journal of Bioethics and the largest Web site in the field, gets eight million hits per month and is ranked between sixth and tenth amongst the highly popular medical sites.

Though medical ethics has been a concern since Hippocrates swore his oath to "First, do no harm," bioethics as a medical discipline did not really exist until 30 years ago. Then, because of growing concern over issues such as abortion and euthanasia, a number of people with religious training began to consult with doctors and hospitals. "The field has been redefined several times," says Glenn McGee, editor in chief of the American Journal of Bioethics. "First, it was religious scholars, then rabbis and priests, then there was the introduction of philosophers." By the late eighties, physicians and lawyers had gotten involved as well.

As a result, there is no clear path to follow for those with a general interest in bioethics. Some are trained in science or medicine first, then take a master's in bioethics; others go to law school. Some start their training with a philosophy Ph.D. and focus on applied ethics - there are only a few Ph.D. programs in bioethics itself. Yet others have degrees in medical anthropology, medical sociology, religious studies, or the history of medicine. And many combine these varied forms of training. For example, Cat Myser, research director at the Tuskegee University National Center for Bioethics in Research and Health Care, has a Ph.D. in philosophy and bioethics from the Kennedy Institute of Ethics at Georgetown University, which is recognized as one of the top programs in the field. Since philosophy departments don't focus on empirical methods - either quantitative or qualitative - Myser also did postdoctoral work in medical anthropology at Stanford.

"The main controversy is what type of background and training is needed to become a bioethicist," says Myser. "The question of credentialing is one of the ugliest ongoing arguments, and is most obvious in clinical ethics [where ethicists work with doctors to help resolve issues in particular cases]."

"Not surprisingly, I think bioethicists should be trained the way I trained. But the way I advise students is to consider what types of work appeal to them. People's training and orientation should be 'transdisciplinary.' By that I mean they need not only to study and have a good grounding in the knowledge and methods of multiple disciplines, but they should be able to speak and understand across disciplines."

Myser has taught in medical schools and practiced clinical ethics for 17 years. One disturbing trend that she has noticed is that doctors and institutions are now more likely to argue in favor of "pulling the plug" on patients for cost reasons rather than reflexively favoring life support. "I was asked by a chief operating officer [of a medical system] to develop a policy for doctors and hospitals to decide unilaterally when additional care is 'futile.' I am an ethicist, I wouldn't be party to that," she says. Myser sees the role of a clinical ethicist as bringing a different perspective to the table - which can be difficult for those who are trained primarily as doctors and may not be able to step outside that role.

"Physicians are trained to advocate for the interests of the patient, but as an ethicist, I'm nobody's advocate. I go in completely open to discussing the values at play. If pushed, of course, I say I advocate for patients and their families, but you would be amazed at how many physicians are unaware of their own subculture and values."

It's necessary to learn the language of the field in which one is working and enough of the science to understand the methods and the implications of the ethical dilemmas, says Myser, but "you aren't there to cut open a heart." Though doctors often believe that they know all they need to know about ethics simply because of their medical experience, a good ethicist can show that there are other points of view and ways of thinking.

For example, at one medical center, Myser found that the doctors who had been offering ethical consulting got three requests for help per year - but she got 115 requests annually. "You show that you understand the clinical reality and that this is a whole other area of expertise," Myser says. "I don't say I have the right moral answers; what I have is tools to make sure you have all the facts, all the value data, and that we are all communicating with each other. Decisions should be made by families, and I try to clear the way for that to happen."

A case she considers one of her greatest successes involved a 13-year-old intellectually disabled girl who came to an Australian hospital 20 weeks pregnant. No one knew who the father of the child was. The girl was being raised by her grandparents, and the doctors were pressing her to have an abortion. "I met with her and it was my job to find out how much she could participate in the decision and help the family to stave off the doctors, who were saying, without medical evidence, that the child might be mentally retarded as well."

The grandparents were pretty much passively agreeing with "the experts," but they began to cry when Myser asked, "What about the fetus?" She learned that there was a long family history of infertility and that the grandparents wanted to help raise the child. The girl delivered a normal baby. "You don't always find out what happens," says Myser. "But you allow the family to do what's best for them, and that's the goal for me."

Erica Rose is director of research and development policy for the United States at GlaxoSmithKline. She came to bioethics by a different route - starting with a B.S. in microbiology from Pennsylvania State University and then getting a law degree from Case Western Reserve University. Rose became interested in bioethics when she heard that the government planned to sequence the human genome. "I felt that there would be significant social, ethical, and legal issues," she explains, "and at the time, I was making decisions about my own educational path. I decided I would like to be involved with issues where policy and science intersect. At the time, there wasn't a real field, but I hoped that there would be."

Rose worked first in the department of microbiology at Hershey Medical Center at Penn State, studying human genetics, and then began working for the U.S. Congress analyzing policy issues related to genetics for the Office of Technology Assessment (since closed). "At the time, Smith Kline Beacham [now GlaxoSmithKline] was looking for someone with experience in genetics as well as policy issues, and there weren't many people who met that description."

"We look at issues that could threaten research activities, or if we are fortunate, that could benefit and encourage biomedical research," she says. Right now, much of her work focuses on medical privacy issues and protecting human subjects.

Like Myser, Rose believes that choosing the right training to become a bioethicist depends mainly on the person's own skills and desires. "I think there is great value in understanding biomedical research if you are going to work in policy development," she says. "As in any area, it's much easier to develop policy if you understand the underlying research."

"There's a lot of critical analysis involved," she says. "That's one thing many people with legal training find attractive. There are a lot of different interests that need to be protected and you want everyone to win." She adds: "I don't know many who do this as a day job. It really does require that you put your heart and soul into overcoming what may seem like insurmountable obstacles. As odd as it sounds, what it requires is analytical thinking and passion."

When asked what she'd say to critics of the pharmaceutical companies, Rose responds, "If people are critical of the industry itself, I don't know how they could ever expect to change it if no one is working internally to bring about change. By my having a role at GSK, I hope to help research move forward and help the industry become one of the leading voices in developing protections for patients and research."

As training programs become more specialized for bioethics, the paths into the field will become more formalized. "We're in a period where we are undergoing a shift from being a multidisciplinary field to an interdisciplinary field," says Magnus. "Right now, we're figuring out what the mix of disciplines within the field should be." With Penn and other schools now offering undergraduate majors and concentrations in bioethics, and with even some high schools offering bioethics courses, he says, "There will be a new generation of people who took bioethics from age 18 or younger and went on to get a Ph.D."

Jokes Tod Chambers, assistant professor of medical ethics and humanities at Northwestern University, whose career path began with religious studies and who has considered issues like surgery on babies born with ambiguous genitalia and the implications of drugs like Prozac: "Eventually, our dream is that there will be a bioethicist in every family."